Vinyl chloroacetate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

other: Expert assessment

Adequacy of study:

weight of evidence

Study period:

09 May 2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Expert assessment based on literature data on the degradation products of VCA

Justification for type of information:

An experimental study to determine the toxicity of VCA to fish was not considered necessary, nor scientifically justified, since the registered substance is expected to undergo rapid abiotic transformation upon contact with water. Therefore the degradation products of VCA were assessed instead in order to calculate an EC50 value for VCA.

Qualifier:

no guideline required

Principles of method if other than guideline:

An expert assessment was performed based on literature data on the degradation products of VCA.

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

ca. 84.084 mg/L

Remarks on result:

other: Expert assessment based on existing literature data on the degradation products

Validity criteria fulfilled:

not applicable

Conclusions:

It is not scientifically necessary to perform a study on the toxicity of VCA to fish, since it degrades rapidly in water to form Chloroacetic acid and Acetaldehyde. The aquatic toxicity of VCA is expected to be driven by the toxicity of these degradation products. The 96 hour LC50 for VCA was calculated to be 84.084 mg/L which is the lowest calculated LC50 value based on literature data across both degradation products.

Executive summary:

 VCA has been found to hydrolyse rapidly (t1/2 12 hrs) upon contact with water to give two main degradation products: Chloroacetic acid (CAS 79-11-8 / EC 201-178-4) and Acetaldehyde (CAS 75-07- 0 / EC 200-836-8). Subsequently, the toxicity of VCA to fish was determined by means of expert assessment, based on the ecotoxicity of its degradation products, for which substantial literature data is already available. A literature search was conducted to obtain a value for the toxicity of Chloroacetic acid and Acetaldehyde to fish. Considering the uses of VCA, it is the toxicity to freshwater species that was considered. The lowest calculated LC50 value was taken from across both degradation products, in order to take the most conservative approach. The degradation product with the lowest EC50 for fish was found to be acetaldehyde with a 96-hour LC50 of 30.8 mg/L obtained on Pimephales promelas. For the purpose of the assessment it was assumed that VCA hydrolyses entirely into the two degradation products. To produce this amount of acetaldehyde, 84.084 mg/L VCA must be hydrolysed. Therefore, it can be concluded that the 96 hour LC50 for the toxicity of VCA to fish is 84.084 mg/L.

Description of key information

It is not scientifically necessary to perform a study on the toxicity of VCA to fish, since it degrades rapidly in water to form Chloroacetic acid and Acetaldehyde. The aquatic toxicity of VCA is expected to be driven by the toxicity of these degradation products. The 96 hour LC50 for VCA was calculated to be 84.084 mg/L which is the lowest calculated LC50 value based on literature data across both degradation products.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

84.084 mg/L